Display on user click is not working

I'm trying to create a 2 step optin for our mailing list. It was working fine until I started trying to do some CSS tweaks to fix the appearance of the popup with my optin form that I created using the optin forms plugin.

The pop up stopped displaying altogether and I can't seem to get it to work. I thought that I'd reversed the CSS tweaks that I did (I edited the width of the popover to be a percentage of the screen so that it would work on smaller screens). It's still not working!

Any help would be much appreciated.

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